489. Решите уравнение: 1) 21(18 + x) = 714; 2) 16(4x - 34) = 608; 3) 12(152 + 19x) = 2052; 4) (152x + 32) * 6 = 192. 490. Решите уравнение: 1) 8(x - 14) = 56; 2) (46-x) * 19 = 418; 3) 9(143-13x) = 234; 4) 17(5x - 16) = 238. 491. Решите уравнение: 1) 14x + 4x - 48 = 240; 2) 25b - 7b - 9 = 279; 3) 16a - 7a + 96 = 222; 4) 20y + 5y + y + 19 = 227. 492. Решите уравнение: 1) 9b + 6b - 15 = 615; 2) 2a + 123a + 97 = 472; 3) 17x - x + 5x - 19 = 170; 4) 73y - y - 22y + 40 = 199 493. Решите уравнение: 1) (x+14) : 9 = 13; 2) 966: (x + 17) = 23; 3) x : 8 - 6 = 49; 4) 52 + 72 : x = 56; 5) 56 : (x-6) = 8; 6) 56 : x - 6 = 8.

489. 1) 21(18 + x) = 714 18 + x = 714 : 21 18 + x = 34 x = 34 - 18 x = 16 2) 16(4x - 34) = 608 4x - 34 = 608 : 16 4x - 34 = 38 4x = 38 + 34 4x = 72 x = 72 : 4 x = 18 3) 12(152 + 19x) = 2052 152 + 19x = 2052 : 12 152 + 19x = 171 19x = 171 - 152 19x = 19 x = 19 : 19 x = 1 4) (152x + 32) * 6 = 192 152x + 32 = 192 : 6 152x + 32 = 32 152x = 32 - 32 152x = 0 x = 0 490. 1) 8(x - 14) = 56 x - 14 = 56 : 8 x - 14 = 7 x = 7 + 14 x = 21 2) (46 - x) * 19 = 418 46 - x = 418 : 19 46 - x = 22 x = 46 - 22 x = 24 3) 9(143 - 13x) = 234 143 - 13x = 234 : 9 143 - 13x = 26 -13x = 26 - 143 -13x = -117 x = -117 : (-13) x = 9 4) 17(5x - 16) = 238 5x - 16 = 238 : 17 5x - 16 = 14 5x = 14 + 16 5x = 30 x = 30 : 5 x = 6 491. 1) 14x + 4x - 48 = 240 18x - 48 = 240 18x = 240 + 48 18x = 288 x = 288 : 18 x = 16 2) 25b - 7b - 9 = 279 18b - 9 = 279 18b = 279 + 9 18b = 288 b = 288 : 18 b = 16 3) 16a - 7a + 96 = 222 9a + 96 = 222 9a = 222 - 96 9a = 126 a = 126 : 9 a = 14 4) 20y + 5y + y + 19 = 227 26y + 19 = 227 26y = 227 - 19 26y = 208 y = 208 : 26 y = 8 492. 1) 9b + 6b - 15 = 615 15b - 15 = 615 15b = 615 + 15 15b = 630 b = 630 : 15 b = 42 2) 2a + 123a + 97 = 472 125a + 97 = 472 125a = 472 - 97 125a = 375 a = 375 : 125 a = 3 3) 17x - x + 5x - 19 = 170 21x - 19 = 170 21x = 170 + 19 21x = 189 x = 189 : 21 x = 9 4) 73y - y - 22y + 40 = 199 50y + 40 = 199 50y = 199 - 40 50y = 159 y = 159 : 50 y = 3,18 493. 1) (x + 14) : 9 = 13 x + 14 = 13 * 9 x + 14 = 117 x = 117 - 14 x = 103 2) 966 : (x + 17) = 23 x + 17 = 966 : 23 x + 17 = 42 x = 42 - 17 x = 25 3) x : 8 - 6 = 49 x : 8 = 49 + 6 x : 8 = 55 x = 55 * 8 x = 440 4) 52 + 72 : x = 56 72 : x = 56 - 52 72 : x = 4 x = 72 : 4 x = 18 5) 56 : (x - 6) = 8 x - 6 = 56 : 8 x - 6 = 7 x = 7 + 6 x = 13 6) 56 : x - 6 = 8 56 : x = 8 + 6 56 : x = 14 x = 56 : 14 x = 4